How Long Will My Money Last in Retirement? An Honest Answer (and How to Find Yours)

If you’re asking how long will my money last in retirement, here’s the honest answer before you read another word: it depends on three things — how much you’ve saved, how much you spend each year, and what the market does, especially in the first decade. That’s it. Anyone who gives you a single magic number without knowing those three things is guessing.

The good news is you don’t have to guess. You can get a personalized estimate with the calculator on this page — it runs your real numbers through several market scenarios in seconds. But a number means little if you don’t understand what’s driving it. So let me walk you through what actually decides how long your savings last, including the one risk almost every free calculator quietly ignores.

The Three Things That Decide How Long Your Money Lasts

Strip away the jargon and your retirement comes down to a simple tug-of-war: money coming in versus money going out, played out over time.

The three levers that matter:

• Your nest egg— the total you’ve actually saved across retirement accounts, brokerage, and cash.
• Your withdrawal rate— the percentage of that nest egg you pull out each year to live on. This is the lever you control most.
• Market returns— how your remaining money grows (or shrinks) while you’re spending it down.

The withdrawal rateis where most people trip up. Take the same $800,000 portfolio. Pull out $32,000 a year (4%) and it can plausibly last 30+ years. Pull out $56,000 (7%) and you’re flirting with portfolio depletionin well under 20 — sometimes much sooner if returns disappoint early. Same starting pile. Wildly different endings. The number you spend matters more than the number you saved.

And one more variable hangs over all of it: life expectancy. Planning to age 85 when you might live to 95 is the difference between a comfortable retirement and an uncomfortable conversation with your kids. This is the assumption people tend to lowball the hardest, because nobody likes planning for a longer life than they expect.

Why Inflation Quietly Shortens Your Timeline

Here’s the thing about inflation— it’s not dramatic. There’s no crash, no headline. It just slowly eats the back half of your retirement while you’re not looking.

Picture spending $5,000 a month today. At a modest 3% inflation rate, that same lifestylecosts roughly $6,700 a month in fifteen years, and close to $9,000 in twenty-five. You didn’t start living larger. The dollar just got smaller.

This is why a flat calculation — “I have $X, I spend $Y, so I’m fine for Z years” — is dangerously optimistic. Your spending isn’t flat. It climbs every single year just to keep you standing in place. A retirement plan that ignores inflation is like a road trip where you only counted the gas for the first half of the drive.

A serious answer to how long will my savings lasthas to grow your spending over time. The calculator above does this automatically, which is why its timeline is often shorter — and more realistic — than the back-of-napkin math most people start with.

The 4% Rule: A Useful Starting Point (and Its Limits)

You’ve probably heard of the 4% rule. It’s the most famous shorthand in retirement planning, and it’s worth understanding — including where it breaks.

The rule came out of research by financial planner William Bengen in the 1990s. The idea: if you withdraw 4% of your portfolio in year one, then adjust that dollar amount for inflation each year after, a balanced portfolio historically survived at least 30 years across almost every market window tested. That’s where the “safe withdrawal rate” label comes from.

It’s a genuinely useful anchor. If you’ve saved $1 million, the 4% rule says roughly $40,000 a year is a reasonable starting draw. Simple, memorable, directionally smart.

But here’s what most people miss about it:

The 4% rule was never a guarantee. It was the worst-case survivorof historical data — and the future doesn’t owe us the past.

A few honest limits:

• It assumes a roughly 30-year retirement. Retire at 55 and you may need a lower rate.
• It assumes a specific stock/bond mix. Sitting too heavy in fixed income or cash changes the math.
• It’s a starting rate, not a rule you robotically follow while your portfolio is clearly cratering.

Treat the 4% rule as a sanity check, not a life plan. It tells you if you’re in the right ballpark. It doesn’t tell you how yourretirement plays out — because it ignores the next thing on this list entirely.

The Risk Most Calculators Ignore: Sequence of Returns

This is the one. If you remember nothing else, remember this, because it’s where the cheap calculators and bank tools fall apart.

Sequence of returns risk means the orderof your returns matters enormously once you’re withdrawing money — even when the average return is identical.

Two retirees can earn the exact same average return over 25 years. One thrives. One runs out of money. The difference? When the bad years showed up.

Think about why. While you’re working and adding money, a market crash is almost a gift — you’re buying cheap. But once you’re retired and sellingassets to live on, a crash early in retirement forces you to sell more shares at low prices to cover the same grocery bill. Those shares are gone. They’re not around to recover when the market bounces back. You’ve locked in the loss permanently.

A 30% drop in your first two years of retirement does far more damage than the identical 30% drop in year fifteen — not because the market behaved differently, but because of when it hit relative to your withdrawals.

The trap most people fall into is averaging. They assume “7% a year” and feel safe. But nobody earns a smooth 7% every year. You get +22%, then −18%, then +9%, in some unknowable order. A simple calculator that uses a flat average rate is blind to this risk — which means it can show you a happy timeline that real market sequences would have wiped out.

That’s exactly why the calculator on this page runs a Monte Carlo stress test— it simulates hundreds of possible return sequences, not one tidy average. It answers the better question: not “what happens if everything goes to plan,” but “in how many realistic futures does my money actually last?”

How to Use This Calculator to Estimate Your Own Number

Enough theory. Here’s how to get your real answer in about two minutes. Plug in:

Then read the three scenarios — conservative, moderate, and optimistic — as a range, not a prediction. Your real life will land somewhere inside that band.

Pay closest attention to the stress test result. If your money lasts in, say, 90% of simulated futures, you’re in a strong spot. If it survives in only half of them, that’s not a reason to panic — it’s an early warning, and it’s far better to see it now than at 78. Adjust your spending or savings and watch the number move. That’s the whole point.

One more thing worth remembering: once you hit your 70s, required minimum distributions (RMDs)force taxable withdrawals from traditional retirement accounts whether you need the cash or not. They affect your timeline and your tax bill, and they’re easy to forget until they hit.

When It’s Worth Talking to a Professional

Let me be straight with you: not everyone needs a financial advisor. If you’re 40, saving steadily, and decades from retiring, a good calculator and some discipline will take you a long way.

But there’s a window where a fiduciary advisor often pays for itself several times over — the five-or-so years on either side of your retirement date. That’s when the irreversible decisions cluster together:

• When to claim Social Security.Remember, it’s designed to replace only about 40% of pre-retirement income for a typical earner, according to the Social Security Administration — so the timing of your claim has outsized weight on the rest of the plan.
• Tax-smart withdrawal order across taxable, tax-deferred, and Roth accounts.
• Managing RMDs and sequence risk in those fragile first retirement years.

These choices are hard to undo. Claim Social Security at the wrong time and you can lock in a smaller check for life. If you’re inside that window and your stress-test results are wobbling, that’s the moment a second set of expert eyes earns its keep.

Get matched with a fiduciary advisor → — someone legally bound to act in your interest, not sell you a product.

Where to Go From Here

The question “how long will my retirement savings last” doesn’t have one answer — it has a range, and that range bends to choices you can still make today. Spend a little less. Save a little more. Claim Social Security a year later. Each lever moves the timeline, and the only way to see by how much is to run your numbers.

So do that now. Scroll up, enter your figures, and read the stress test honestly. Then decide whether your next move is a small adjustment — or a conversation with a pro.

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This article is for educational purposes only and is not financial advice. Everyone’s situation is different. See our full disclaimer.